The Biostatistics Core (Core B) has been involved in the lithotripsy program project since its inception, providing data management expertise and statistical support to the team of multidisciplinary researchers In assessing the impact of shock wave lithotripsy on renal function and developing new treatment protocols . The specific alms for the Statistics Core for the next five years are: Aim 1: Provide statistical support to Investigators of this program project to ensure that appropriate study design and sufficient sample sizes with adequate statistical power are used in all experiments. Aim 2: Conduct statistical analyses of experimental data ensuring appropriate statistical models and techniques are used in analyzing each data set. Provide statistical support for accurate presentation of analysis results in reports and publications. Aim 3: Develop new statistical methodology to address challenging statistical issues related to both experimental design and data analyses that arise from this research program. The continued involvement of the Biostatistics Core in this research project will ensure that all experiments are conducted with appropriate design and adequate sample size, data are analyzed with appropriate statistical technique, and results are presented accurately with sufficient statistical details.